The method and system of this invention were developed for use in an aircraft as a control for an ejection seat. However, the invention is not limited to aircraft but also has application to aerospace planes and space vehicles. Also, the method and system of the invention have been applied in design studies to aircraft escape capsules. Accordingly, the term "flying vehicle" is used herein to mean either an aircraft or an aerospace craft or a space craft and the term "escape device" is used to mean any type of crewmember carrying device which is separated from the vehicle as a part of a crewmember escape operation.
Generally, a crewmember escape operation for an ejection seat is as follows:
An escape path is cleared, such as by the opening or removal of a canopy, escape hatch, or other barrier on the vehicle, in the escape path of the escape device. Then, the escape device is separated (e.g. ejected or catapulted) from the vehicle. If at the time of separation the escape device is in an upright position, the escape device is ejected vertically upwardly. If the escape device is at that time high enough above the ground for safe deployment of a parachute, a parachute may be opened and used for lowering the crewmember to the ground. However, usually the escape device is flown to a higher altitude to avoid collision with the vehicle and then the parachute is opened. If at the time of separation the escape device is in a leaning attitude, or is upside down, and more elevation is needed, the escape device is rotated into an upright position while being flown to a higher altitude.
U.S. Pat. No. 3,191,892, granted June 29, 1965, to Harold R. Fuller and James L. Greene, Jr., discloses an ejection system which functions to catapult the seat and crewman out of the aircraft, and then immediately open a parachute, for bringing the crewmember safely to the ground. U.S. Pat. No. 3,186,662, granted June 1, 1985, to James Martin, and U.S. Pat. No. 4,216,928, granted Aug. 12, 1980, to John O. Hooper, W. James Stone and Vernon D. Burklund, both disclose an ejection seat system in which the seat is provided with thruster means for flying the seat following its separation from the aircraft. In U.S. Pat. No. 4,216,928, the patentees state that their system capability is such that a low altitude, inverted ejection results in a reverse in seat direction after initially clearing the aircraft so that the pilot will not impact with the earth but rather will be moved upwardly to an altitude at which his parachute can be safely deployed. FIG. 5 of this patent graphically illustrates a low altitude, inverted ejection.
U.S. Pat. No. 4,236,687, granted Dec. 2, 1980, to W. James Stone and Lovic P. Thomas, also discloses an ejection seat having a thruster for flying the seat following seat separation from the aircraft. The thruster includes a gimbaled nozzle and a control system for moving the nozzle, to provide pitch, roll and yaw control of the ejection seat.
U.S. Pat. No. 4,437,628, granted Mar. 20, 1984, to Marcus Schwartz discloses a torso haul back system for an ejection seat. This patent also makes reference to an explosive bolt system for jettisoning the cockpit canopy of an aircraft.
Examples of other ejection seat systems in the patent literature are disclosed by the following U.S. patent : U.S. Pat. No. 2,892,602, granted June 30, 1959, to Lucien Servanty; U.S. Pat. No. 2,996,272, granted Aug. 15, 1961, to Albert M. Stott and Norman J. Waecker; U.S. Pat. No. 3,311,330, granted Mar. 28, 1967, to James E. Hofferberth and John B. Morris; U.S. Pat. No. 3,530,868, granted Sept. 29, 1970, to Michael A. Rickards; U.S. Pat. No. 3,862,731, granted Jan. 28, 1975, to Robert G. McIntyre; U.S. Pat. No. 4,057,206, granted Nov. 8, 1977, to James W. Duncan and Walter R. Peck; U.S. Pat. No. 4,395,001, granted July 26, 1983, to W. James Stone, Vernon D. Berklund and Robert B. Dillinger; U.S. Pat. No. 4,396,171, granted Aug. 2, 1983, to Edwin R. Schultz; U.S. Pat. No. 4,448,374, granted May 15, 1984, to James W. Duncan; U.S. Pat. No. 4,505,444, granted Mar. 19, 1985, to John S. Martin; and U.S. Pat. No. 4,527,758, granted July 9, 1985, to Peter Ayoub and Alan Cantor. All of the above patents, and the prior art discussed and/or cited in the patents, should be considered for the purpose of putting the present invention into proper perspective relative to the prior art.